Armor Class Calculator 5e

Your essential tool for calculating Armor Class in Dungeons & Dragons 5th Edition.

Total Armor Class

15

Breakdown:

AC Contribution Chart

Visual breakdown of what contributes to your total Armor Class.

AC by Dexterity and Armor Type

Dexterity Modifier	Unarmored AC	Light Armor (Studded Leather, 12)	Medium Armor (Half Plate, 15)	Heavy Armor (Plate, 18)
-1 (8-9 Dex)	9	11	14	18
+0 (10-11 Dex)	10	12	15	18
+1 (12-13 Dex)	11	13	16	18
+2 (14-15 Dex)	12	14	17	18
+3 (16-17 Dex)	13	15	17	18
+4 (18-19 Dex)	14	16	17	18
+5 (20-21 Dex)	15	17	17	18

This table shows example AC values based on common armor types and a character’s Dexterity modifier. Shield and other bonuses are not included.

What is an Armor Class Calculator 5e?

An Armor Class (AC) calculator for Dungeons & Dragons 5th Edition is a specialized tool designed to determine one of the most crucial combat statistics for a character. Armor Class represents how difficult it is for an opponent to land a successful hit on you. A higher AC means attacks are more likely to miss. This armor class calculator 5e simplifies the process, which can sometimes be complex due to the various rules and modifiers involved. [4]

This calculator is for anyone playing D&D 5e, from new players creating their first character to veteran Dungeon Masters who need to quickly calculate the AC for a non-player character (NPC). It takes into account your base armor, Dexterity, shield, and special abilities like a Monk’s Unarmored Defense, which you can learn more about in a d&d 5e character builder.

The Formula Behind Armor Class in 5e

There isn’t one single formula for AC, but rather a set of formulas you choose from based on what your character is wearing or what abilities they have. You can only benefit from one calculation at a time. [1] Our armor class calculator 5e automatically selects the right one for you.

The primary calculation methods are:

• Unarmored: AC = 10 + Dexterity Modifier [2]
• Light Armor: AC = Armor’s Base AC + Dexterity Modifier [3]
• Medium Armor: AC = Armor’s Base AC + Dexterity Modifier (but the bonus from Dexterity cannot exceed +2) [14]
• Heavy Armor: AC = Armor’s Base AC (your Dexterity modifier is not added, but you are not penalized for a negative one either) [7]
• Unarmored Defense (Barbarian): AC = 10 + Dexterity Modifier + Constitution Modifier [1]
• Unarmored Defense (Monk): AC = 10 + Dexterity Modifier + Wisdom Modifier [1]
• Mage Armor (Spell): AC = 13 + Dexterity Modifier [9]

After finding your base AC with one of these formulas, you add bonuses from shields (+2) and any other sources like magic items or spells. You can find more detail on this in guides to how to calculate AC 5e.

AC Calculation Variables

Variable	Meaning	Unit / Type	Typical Range
Base AC	The starting value provided by the armor worn.	Points	11 (Padded) to 18 (Plate). [8]
Ability Score Modifier	A bonus or penalty derived from a core stat (Dex, Con, Wis).	Modifier	-1 to +5 for most characters.
Shield	A flat bonus for carrying a shield.	Bonus	+2
Other Bonuses	Miscellaneous bonuses from spells, magic, or feats.	Bonus	+1 to +3 or more.

Practical Examples

Example 1: A Nimble Rogue

A Rogue with a Dexterity score of 18 (+4 modifier) is wearing Studded Leather Armor (Base AC 12). They are not using a shield.

• Inputs: Light Armor, Base AC 12, Dexterity 18, No Shield, 0 Other Bonuses.
• Calculation: 12 (from armor) + 4 (from Dexterity modifier).
• Result: Their total Armor Class is 16.

Example 2: A Sturdy Fighter

A Fighter with a Strength of 16 and Dexterity of 10 (+0 modifier) is wearing full Plate Armor (Base AC 18). They are carrying a shield and have a Ring of Protection (+1 AC).

• Inputs: Heavy Armor, Base AC 18, Dexterity 10, Shield, +1 Other Bonus.
• Calculation: 18 (from Plate armor) + 2 (from shield) + 1 (from ring). The Dexterity modifier does not apply to heavy armor.
• Result: Their total Armor Class is 21. For more on feats like the heavy armor master feat, check our guides.

How to Use This Armor Class Calculator 5e

Using this calculator is a straightforward process:

1. Select Your AC Method: Start by choosing your primary method of AC calculation from the dropdown. This is the most important step. Are you wearing armor, or are you a Barbarian using Unarmored Defense?
2. Enter Base AC (If Applicable): If you are wearing Light, Medium, or Heavy armor, enter the base AC value found in the Player’s Handbook. This field is hidden if it’s not needed.
3. Input Ability Scores: Enter your character’s total ability scores (not just the modifier). The calculator will automatically show fields for Constitution or Wisdom if you select a Monk or Barbarian.
4. Check for a Shield: Tick the checkbox if your character is using a shield for a standard +2 bonus.
5. Add Other Bonuses: Input the sum of any other bonuses you might have from spells like Shield of Faith, magic items, or class features.
6. Review Your AC: The calculator instantly updates your total AC and provides a breakdown of where each point comes from.

Key Factors That Affect Armor Class

Several factors can increase or decrease your AC. Understanding them is key to building a resilient character. Our dnd combat rules guide has more.

• Armor Type: The fundamental choice. Light armor favors high Dexterity, while Heavy armor provides high AC with no Dexterity requirement. [18]
• Dexterity Modifier: How nimble you are. It’s crucial for unarmored and light-armored characters. [6]
• Shields: A simple and effective way to get a +2 AC bonus, but it requires a free hand.
• Class Features: Barbarians and Monks have the special “Unarmored Defense” feature, which uses their Constitution or Wisdom for protection. [4]
• Spells: Magical effects can provide powerful, often temporary, boosts to AC. Examples include Shield, Shield of Faith, and the mage armor spell.
• Magic Items: Enchanted armor, shields, rings (Ring of Protection), and cloaks (Cloak of Protection) can provide permanent “plus” bonuses to your AC.
• Feats: Certain feats like Defensive Duelist or Heavy Armor Master can directly or indirectly improve your defensive capabilities.
• Cover: Hiding behind an obstacle can grant you a bonus to AC (+2 for half cover, +5 for three-quarters cover).

Frequently Asked Questions (FAQ)

1. How is the Dexterity modifier calculated?

The modifier is calculated from your Dexterity score. The formula is: floor((Score – 10) / 2). A score of 10-11 is a +0 modifier, 12-13 is +1, 14-15 is +2, and so on.

2. Can I use a shield with Unarmored Defense?

A Barbarian can use a shield with their Unarmored Defense. However, a Monk’s Unarmored Defense feature specifies that it only works if they are not wearing armor or wielding a shield. [22]

3. What happens if my Dexterity modifier is negative?

If your Dex modifier is negative, it will reduce your AC when wearing no armor, light armor, or medium armor. Heavy armor is a special case; it does not penalize you for a negative Dexterity modifier. [7]

4. Do bonuses from multiple spells stack?

Generally, no. Effects from two different spells don’t stack if they have the same name. Also, if two effects give you different ways to calculate your AC (like Mage Armor and a Monk’s Unarmored Defense), you must choose which one to use; you cannot combine them. [1]

5. What does the “max +2” for medium armor mean?

It means that even if your Dexterity modifier is +3, +4, or higher, you can only add a maximum of +2 to your AC when wearing medium armor. [14]

6. Does my proficiency bonus get added to my AC?

No. You do not add your proficiency bonus to your Armor Class. Being proficient with a type of armor simply means you know how to wear it effectively and avoid penalties, like not being able to cast spells. [15]

7. Can a Barbarian/Monk multiclass stack Unarmored Defense?

No. The rules on multiclassing and AC calculations are clear that features that provide a new way to calculate AC are mutually exclusive. You must choose to use either the Barbarian’s formula (using Constitution) or the Monk’s (using Wisdom), you cannot use both. [16]

8. Is there a maximum possible AC?

Theoretically, there’s no hard cap, but it’s limited by the available items, spells, and stats in the game. Reaching an AC above 25 is very difficult and usually involves a combination of powerful legendary magic items and high-level spells.

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